This invention generally relates to a method and apparatus for sterilization of objects and goods, and particularly to a method and apparatus for sterilization in an atmosphere of gaseous water and electromagnetic energy in the microwave range at lower temperatures and shorter periods than those presently used to kill potential pathogens.
That mankind is continuing to evolve is a perceptive fact. As any species makes progress, it encounters new hazards and must adapt or gain the dubious distinction of being placed on a list. The brutal fact is that Mother Nature gives very few tests, but they are all finals.
The doctor, the dentist, and the restaurant owner would all assure you that Mother Nature would not give you her finals if they had a very fast, very sure, sterilizer. Sterilizers are no substitute for good housekeeping, but a sterilizer could insure that your doctor, your dentist, or your eating utensils didn't inoculate you. The vulnerability to hazards increases when you journey into the world. But, only because the scientific area of sterilizers has been neglected.
The continual increase in the mobility of mankind and the changes in lifestyles has heightened the need for a commonplace practice to prevent the inoculation of gross segments of the population with potential pathogens. Sterile practices have expanded from the surgical sight to other areas of potential inoculation but not nearly at a pace adequate to isolate pathogenic outbreaks. The primary reason for the failure of sterile practices to keep pace with the expanding need is a complex combination of factors including: the reluctance to admit that a problem exists, the current cumbersome solutions to the problem, the insensitivity of the regulatory agencies, cost, and the absence of a viable alternative to current cumbersome processes.
At present, the old fashioned steam sterilizer is still the workhorse employed by those concerned with sterile practices. With each problem encountered, the art of sterile practice has added a solution to the process in order to solve that problem. Autoclaves require that low heat transfer air be removed from the cavity. The solution to this problem has been to add an evacuation cycle or a repetitive gravity displacement cycle to remove the air. Another problem with autoclaves is that the sterilized load is wet after being sterilized. Wet loads provide a ready avenue for reinfestation by potential pathogens. The solution to this problem has been to add a drying cycle to the autoclave. By adding solutions to solve these inherent problems, the cycle time of the autoclave has lengthened the total time from cycle to cycle. Slow, cumbersome operation has limited the autoclave operation to the necessary only. Thus, these autoclaves are slow, expensive pressure vessels which require regular inspections from several agencies. In addition, the autoclave is destructive to many plastics.
For more than ten years, microwave energy has been known to cause near instant death to all virus and bacteria. Yet, there is not a microwave sterilizer on the market for three major reasons, namely: 1. the inability of microwave energy to kill dry spores; 2. the inability of the science to create a uniform energy field; and 3. the tendency to self destruct from its own energy.
It is, therefore, an object of this invention to provide a novel chamber for sterilizing eating utensils, laboratory instruments, medical and dental tools, and other goods through the application of water vapor and microwave energy.
It is further an object of this invention to provide such a novel sterilizing chamber which sterilizes at far lower general temperatures than those encountered in the conventional autoclave or dry sterilizers to allow for the sterilization of numerous low melting point materials.
It is further an object of this invention to provide such a novel sterilizing chamber which sterilizes at a faster general rate than those encountered in the conventional autoclave or dry sterilizers.
It is further an object of this invention to provide such a novel sterilizing chamber having differential temperature points to control the location of water quantities within the sterilizer chamber through selective condensation to prevent the potential for recontamination of the sterilized load along wet paths in the load.
It is further an object of this invention to provide such a novel sterilizing chamber which forms a synergy of steam and microwave energy to cause rapid sterilization.
It is further an object of this invention to provide such a novel sterilizing chamber which causes rapid sterilization with or without the requirement of a pressure chamber.
It is further an object of this invention to provide such a novel sterilizing chamber which prevents the self-destruction of the microwave source by trapping reflected energy in a parallel load.
It is further an object of this invention to provide such a novel sterilizing chamber which sterilizes objects without destruction of their sharp working points or edges by arcing.
It is further an object of this invention to provide such a novel sterilizing chamber which alters the standing waves in the sterilizing chamber in response to the condition of the working covity and/or load to be sterilized.
These and further objects and advantages of the present invention will become clearer in light of the following detailed description of an illustrative embodiment of this invention described in connection with the drawings.